Project Summary/Abstract Repeat concussions are a growing concern for adolescents and young adult athletes. Experimentally one of the problems is that no one has been addressing this in an ?athlete? model. Growing evidence shows that the brains of those that exercise regularly (athletes) are very different than those that are sedentary. These differences will affect how the ?athlete brain? responds to concussive injuries. In this application we have developed a rathlete model to study the effects of concussive injuries and recovery between the athlete brain and non-athlete brain in both male and female rats. This work will not only provide important information regarding brain injury research, but emphasize the role of exercise in adolescent health.